Gold nanoparticles supported on Al₂O₃ using Tabebuia aurea leaf extract and catalytic properties for methylene blue reduction

In this research, we reported a cost-effective and an environmentally friendly technique for synthesis of gold nanoparticles supported on alumina (Al₂O₃/AuNPs) using Tabebuia aurea leaf extract (TAE) as non-toxic reducing agent, efficient stabilizer, and weak base source without adding any surfactants. Al₂O₃/AuNPs was characterized using various techniques including UV-Visible Spectrophotometer, Fourier-transform Infrared (FT-IR) spectroscopy, X-Ray diffraction (XRD), and Particle Size Analyzer (PSA). AuNPs was successfully synthesized using HAuCl₄ as precursor. The characterization of UV-Vis Spectrophotometer shows that AuNPs colloidal was formed at 0.15 % TAE. FTIR characterization of Al₂O₃ shows Al-OH band at 1505 cm^-1 and Al-O band at 680 cm^-1. Phase of Al₂O₃ was amorphous confirmed by XRD. The particle size distribution average of Al₂O₃/AuNPs was about 43 nm. The reduction percentage of methylene blue using Al₂O₃/AuNPs catalyst was 70.41 % for 120 min.